N-AROYL CYCLIC AMINES

1 . A compound of formula (Ia):

wherein:

Y represents a bond or a group (CH 2 ) n , wherein n represents 1;

Ar 1 is benzoxazolyl, benzothiazolyl, or benzimidazolyl;

Ar 2 represents a phenyl group or a 5- or 6-membered heterocyclyl group selected from furanyl, thienyl, pyrrolyl, oxazolyl, thiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, pyridyl, triazolyl, triazinyl, pyridazinyl, pyrimidinyl, isothiazolyl, isoxazolyl, pyrazinyl, and pyrazolyl, and wherein the phenyl or heterocyclyl group is substituted by R 1 and is further optionally substituted, or

Ar 2 represents an optionally substituted naphthyl group or optionally substituted bicyclic heteroaromatic group selected from benzofuryl, benzimidazolyl, quinolinyl, quinoxalinyl, benzotriazolyl, benzothienyl, benzoxazolyl, naphthyridinyl, isoquinolyl, quinazolinyl, indolyl, benzothiazolyl, and benzothiadiazolyl;

R 1 represents hydrogen, optionally substituted (C 1-4 )alkoxy, halo, cyano, optionally substituted (C 1-6 )alkyl, or an optionally substituted phenyl;

wherein said optionally substituted Ar 1 , Ar 2 , and R 1 is optionally substituted by halogen, hydroxy, oxo, cyano, nitro, (C 1-4 )alkyl, (C 1-4 )alkoxy, hydroxy(C 1-4 )alkyl, hydroxy(C 1-4 )alkoxy, halo(C 1-4 )alkyl, halo(C 1-4 )alkoxy, aryl(C 1-4 )alkoxy, (C 1-4 )alkylthio, hydroxy(C 1-4 )alkyl, (C 1-4 )alkoxy(C 1-4 )alkyl, (C 3-6 )cycloalkyl(C 1-4 )alkoxy, (C 1-4 )alkanoyl, (C 1-4 )alkoxycarbonyl, (C 1-4 )alkylsulfonyl, (C 1-4 )alkylsulfonyloxy, (C 1-4 )alkylsulfonyl(C 1-4 )alkyl, arylsulfonyl, arylsulfonyloxy, arylsulfonyl(C 1-4 )alkyl, (C 1-4 )alkylsulfonamido, (C 1-4 )alkylamido, (C 1-4 )alkylsulfonamido(C 1-4 )alkyl, (C 1-4 )alkylamido(C 1-4 )alkyl, arylsulfonamido, arylcarboxamido, arylsulfonamido(C 1-4 )alkyl, arylcarboxamido(C 1-4 )alkyl, aroyl, aroyl(C 1-4 )alkyl, aryl(C 1-4 )alkanoyl, (C 1-4 )acyl, aryl, aryl(C 1-4 )alkyl, (C 1-4 )alkylamino(C 14 )alkyl, R a R b N—, R a OCO(CH 2 ) r , R a CON(R a )(CH 2 ) r , R a R b NCO(CH 2 ) r , R a R b NSO 2 (CH 2 ) r or R a SO 2 NR b (CH 2 ) r , wherein r represents zero or an integer from 1 to 4, or R a R b N(CH 2 )n- or R a R b N(CH 2 )nO-, wherein n represents an integer from 1 to 4, wherein each of R a and R b independently represents a hydrogen atom or a (C 1-4 )alkyl group or R a R b forms part of a (C 3-6 )azacycloalkane or (C 3-6 )(2-oxo)azacycloalkane ring, or R a R b N(CH 2 )n- or R a R b N(CH 2 ) n O, where R a with at least one CH 2 of the (CH 2 )n portion of the group form a (C 3-6 )azacycloalkane and R b represents hydrogen, a (C 1-4 )alkyl group or with the nitrogen to which it is attached forms a second (C 3-6 )azacycloalkane fused to the first (C 3-6 )azacycloalkane;

wherein when Y is a bond then Ar 2 can not be 2-naphthyl;

or a pharmaceutically acceptable salt thereof.

2 . A compound according to claim 1 , wherein Ar 2 represents an optionally substituted phenyl, pyridyl, thiazolyl, pyrazolyl, benzofuryl, naphthyl, triazolyl, quinoxalinyl, quinolinyl, isoquinolinyl, benzimidazolyl, benzothienyl, benzotriazolyl, benzothiazolyl, indolyl or thienyl.

3 . A compound according to claim 1 , wherein Ar 2 represents an optionally substituted phenyl, pyridyl, thiazolyl, pyrazolyl, triazolyl, or thienyl.

4 . A compound according to claim 1 , wherein R 1 is selected from a trifluoromethoxy, methoxy, ethoxy, halo, cyano or an optionally substituted phenyl, pyridyl, pyrazolyl, pyrimidinyl, and oxadiazolyl group.

5 . A pharmaceutical composition comprising a therapeutically effective amount of the compound according to claim 1 , or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.

6 . A method of treating a disease or disorder where an antagonist of a human orexin receptor is required, which comprises administering to a subject in need thereof an effective amount of the compound according to claim 1 , or a pharmaceutically acceptable salt thereof, wherein said disease or disorder is selected from obesity and obesity associated with Type II diabetes.

7 . A method of treating insomnia which comprises administering to a subject in need thereof an effective amount of the compound according to claim 1 , or a pharmaceutically acceptable salt thereof.

8 . A compound selected from:

1-[2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-methyl-5-phenyl-thiazol-4-yl)-methanone;

1-[2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-biphenyl-2-yl-methanone;

1-[2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-[2-(3-methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone;

1-[2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-trifluoromethoxy-phenyl)-methanone;

1-[2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-naphthalen-1-yl-methanone;

1-[2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-methoxy-phenyl)-methanone;

1-[2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-iodo-phenyl)-methanone;

1-[(S)-2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-trifluoromethoxy-phenyl)-methanone;

1-[(S)-2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-[2-(3-methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone;

1-[(S)-2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-biphenyl-2-yl-methanone;

1-[(S)-2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-iodo-phenyl)-methanone

1-[2-Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-phenyl-methanone;

1-{2-[(1H-Benzoimidazol-2-ylamino)-methyl]-piperidin-1-yl}-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone;

1-{2-[(1H-Benzoimidazol-2-ylamino)-methyl]-piperidin-1-yl}-1-[2-(3-methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone;

1-[2-(Benzothiazol-2-ylaminomethyl)-piperidin-1-yl]-1-[2-(3-methyl-[1,2,4]oxadiazol-5-yl)-phenyl]-methanone;

1-[2-(Benzothiazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-trifluoromethoxy-phenyl)-methanone;

1-[2-(Benzothiazol-2-ylaminomethyl)-piperidin-1-yl]-1-biphenyl-2-yl-methanone;

1-[2-(Benzothiazol-2-ylaminomethyl)-piperidin-1-yl]-1-(2-methyl-5-phenyl-thiazol-4-yl)-methanone;

1-[(S)-2-(Benzooxazol-2-ylaminomethyl)-piperidin-1-yl]-1-[5-(4-fluoro-phenyl)-2-methyl-thiazol-4-yl]-methanone;

1-[2-(Benzothiazol-2-ylaminomethyl)-piperidin-1-yl]-1-naphthalen-1-yl-methanone;

1-(1H-Benzoimidazol-5-yl)-1-[(S)-2-(pyrido[2,3-b]pyrazin-2-ylaminomethyl)-piperidin-1-yl]-methanone;

1-Benzo[b]thiophen-2-yl-1-{(S)-2-[(6,7-difluoro-quinoxalin-2-ylamino)-methyl]-piperidin-1-yl}-methanone;

1-(1H-Benzoimidazol-5-yl)-1-{(S)-2-[(6,7-difluoro-quinoxalin-2-ylamino)-methyl]-piperidin-1-yl}-methanone;

1-(1H-Benzotriazol-5-yl)-1-{(S)-2-[(6,7-difluoro-quinoxalin-2-ylamino)-methyl]-piperidin-1-yl}-methanone;

1-Benzothiazol-6-yl-1-{(S)-2-[(6,7-difluoro-quinoxalin-2-ylamino)-methyl]-piperidin-1-yl}-methanone;

2-{[(S)-1-(1-1H-Benzoimidazol-5-yl-methanoyl)-piperidin-2-ylmethyl]-amino}-6,7-difluoro-quinoline-3-carbonitrile;

2-{[(S)-1-(1-Benzothiazol-6-yl-methanoyl)-piperidin-2-ylmethyl]-amino}-6,7-difluoro-quinoline-3-carbonitrile;

1-(1H-Benzoimidazol-5-yl)-1-{(S)-2-[(5-bromo-pyrimidin-2-ylamino)-methyl]-piperidin-1-yl}-methanone;

and a pharmaceutically acceptable salt thereof.